Sunday, March 10, 2024

Sharks, turtles and other sea creatures face greater risk from industrial fishing than previously thought − we estimated added pressure from ‘dark’ fishing vessels

Seabirds like this sooty shearwater can drown when they become tangled in drift nets and other fishing gear. Roy Lowe, USFWS/Flickr, CC BY
Heather Welch, University of California, Santa Cruz

My colleagues and I mapped activity in the northeast Pacific of “dark” fishing vessels – boats that turn off their location devices or lose signal for technical reasons. In our new study, we found that highly mobile marine predators, such as sea lions, sharks and leatherback sea turtles, are significantly more threatened than previously thought because of large numbers of dark fishing vessels operating where these species live.

While we couldn’t directly watch the activities of each of these dark vessels, new technological advances, including satellite data and machine learning, make it possible to estimate where they go when they are not broadcasting their locations.

Examining five years of data from fishing vessel location devices and the habitats of 14 large marine species, including seabirds, sharks, turtles, sea lions and tunas, we found that our estimates of risk to these animals increased by nearly 25% when we accounted for the presence of dark vessels. For some individual predators, such as albacore and bluefin tunas, this adjustment increased risk by over 36%. The main hot spots were in the Bering Sea and along the Pacific coast of North America.

Bycatch, or accidental take, is the leading threat to some endangered marine species.

How we did our work

Fishing boats use Automatic Identification System, or AIS, to avoid colliding with each other. Their AIS signals bounce off satellites to reach nearby ships.

This data is a valuable tool for mapping risk at sea and understanding the footprints of fishing fleets. AIS data captures an estimated 50% to 80% of fishing operations occurring more than 100 nautical miles from shore.

But in some areas, vessels’ AIS signals can’t reach the satellites, either because reception is poor or many boats are crowded together – much as cellphones can have difficulty sending text messages in remote wildness or in crowded stadiums. And just as location tracking can be disabled on phones, fishing vessels can intentionally disable their AIS if they want to hide their location. Boats that do this may be engaged in criminal activities, such as illegal fishing or human trafficking.

We calculated how much risk dark vessels pose to marine life by overlapping their activity with the modeled habitats of 14 highly mobile marine predators. Using the same method, we also calculated how much risk observable fishing vessels that broadcast their locations pose to marine life. These two calculations allowed us to understand the additional risk from dark fishing vessels.

A seal on a beach, with a rope wrapped around it and connected to a large orange float beside the animal.
A Hawaiian monk seal entangled on a large fishing float. Doug Helton, NOAA/NOS/ORR/ERD, CC BY

Why it matters

We know that many sea creatures, including endangered species, are killed by overfishing, accidental catch and entanglement in fishing gear. More overlap between wildlife and fishing boats means that those harmful impacts are more likely to happen.

Even considering only observable fishing boats broadcasting their positions, the presence of boats signals considerable risk for marine life. For example, California sea lions forage in Pacific coastal waters from the Canadian border to Baja California and are accidentally caught by boats fishing for hake and halibut. We found observable fishing activity in over 45% of the sea lions’ habitat.

In another example, migratory salmon sharks feed on salmon near Alaska’s Aleutian Islands during the summer and breed in warmer waters off the coasts of Oregon and California during the winter. Along their journey, salmon sharks are accidentally caught in fishing nets and longlines. We detected observable vessel fishing activity in nearly one-third of salmon shark habitat.

Dozens of fishing boats move out of an urban harbor
Fishing boats head out for the East China Sea in Zhoushan, Zhejiang Province, China. Shen Lei/VCG via Getty Images

Our findings indicate that such threats are higher when dark fishing boats are present. Estimates of risk to California sea lions and salmon sharks increased by 28% and 23%, respectively, when we accounted for dark vessels.

This information could affect fishery regulation. For example, regulators use risk information to set catch limits for species such as tuna; higher risk could mean that catch limits need to be lower.

For species such as sea lions and salmon sharks that are accidentally caught by fishermen, higher risk levels could indicate that fishing boats should use more selective gear. California is currently acting on this issue by helping fishermen phase out use of large-mesh drift gill nets in state waters. These nets, which hang like curtains in the water, catch many other fishes along with the target species.

Accounting for dark vessels is particularly important in international waters where boats from multiple countries operate, because AIS data is one of the most complete sources of fishing activity across nations. Tracking dark vessels can help make this information as comprehensive as possible and provide insights into the multinational impacts of fishing.

Our study does not account for vessels that do not use any vessel tracking system, or that use systems other than AIS. Therefore, our risk calculations likely still underestimate the true impact of fisheries on marine predators.

What’s next

The world’s oceans are rich in life but poor in data, although this is changing. High-resolution satellite imagery may soon offer even more information on risk from dark vessels.

President Joe Biden and other global leaders have pledged to protect 30% of the ocean by 2030. Better data on human-wildlife interactions at sea can help ensure that new protected areas are in the right places to make a difference.The Conversation

Heather Welch, Researcher in Ecosystem Dynamics, University of California, Santa Cruz

This article is republished from The Conversation under a Creative Commons license. 

Friday, March 8, 2024

The atomic bomb, exile and a test of brotherly bonds: Robert and Frank Oppenheimer

A rift in thinking about who should control powerful new technologies sent the brothers on diverging paths. For one, the story ended with a mission to bring science to the public.

Every now and then, science serves up poison pills. Knowledge gained in the course of exploring how nature works opens doors we might wish had stayed shut: For much of the past year, our newsfeeds were flooded with stories about how computational superpowers can create amoral nonhuman “minds” that may learn to think better than we do (and then what?). On the big screen, the movie Oppenheimer explored a threat people have lived with for nearly 80 years: How the energy of the atom can be unleashed to power unimaginably destructive bombs.

When potentially catastrophic inventions threaten all humanity, who decides how (or whether) they’re used? When even scientists toss around terms like “human extinction,” whose voice matters?

Such questions were at the core of the Oppenheimer film, a blockbuster now nominated for more than a dozen Oscars. To me, the movie hit home for a different reason. I spent a great deal of time with Frank Oppenheimer during the last 15 years of his life. While I never knew his brother Robert, Frank remained anguished over what he felt was Robert’s squandered opportunity to engage the world’s people in candid conversations about how to protect themselves under the shadow of this new threat.

During the post-World War II years, the emotionally close ties between the brothers (Robert — the “father of the atom bomb” — and his younger brother, Frank — the “uncle” of the bomb, as he mischievously called himself) were strained and for a time even fractured. Both hoped that the nascent nuclear technology would remain under global, and peaceful, control. Both hoped that the sheer horror of the weapons they helped to build could lead to a warless world.

They were on the same side, but not on the same page when it came to tactics.

Robert — whose fame surged after the war — believed decisions should be left to experts who understood the issues and had the power to make things happen — that is, people like himself. Frank believed just as fiercely that everyday people had to be involved. It took everyone to win the war, he argued, and it would take everyone to win the peace.

In the end, both lost. Both paid for their efforts with their careers (although Frank eventually resurrected his ideas as a “people’s science museum” that had a worldwide impact).

Given that the question “Who decides?” underlies so much of today’s fast-evolving sciences, the brothers’ story seems more compelling and relevant than ever.

Ethical education

In many ways, the Oppenheimer brothers were very much alike. Both studied physics. Both chain-smoked. Both loved art and literature. Both had piercing blue eyes, inherited from their mother, Ella Friedman Oppenheimer, an artist with a malformed hand always hidden in a glove. Their father, Julius, was a trustee of the Society for Ethical Culture, dedicated to “love of the right.”

They shared a Manhattan apartment with maids, Renoirs, and books piled down the halls and into the bathrooms. Ella was terrified of germs, so tutors and barbers often came to them. Frank had his tonsils out in his bedroom. Both boys attended Ethical Culture schools in New York, so morality was baked into their upbringing.

But they were also in other ways opposites.

Robert was, by his own admission, “an unctuous, repulsively good little boy.” Frank was anything but. He sneaked out at night to scale New York City’s rooftop water towers; by high school, he was using the electric current in the family home to weld whatever metal he could get his hands on. He took apart his father’s player piano (then stayed up all night putting it back together).

Robert got through Harvard in three years and received his PhD from the University of Göttingen two years later, in 1927, at age 23. Frank didn’t get his PhD until he was 27. Robert was arrogant, picky about his company. Frank would talk with anyone and did, later befriending even his FBI tail.

When Robert joined the faculty at Caltech, he was described as “a sort of patron saint,” always center stage, smooth, articulate, captivating. When Frank arrived at Caltech many years later for graduate work, he was described as standing “at the fringe, shoulders hunched over, clothes mussed and frayed, fingers still dirty from the laboratory.”

Still, they loved each other dearly. Frank wept when Robert left for grad school in Europe. Robert wrote Frank that he would gladly give up his vacation “for one evening with you.” He sent his little brother books on physics and chemistry, a sextant, compasses, a metronome, along with letters full of brotherly wisdom. My personal favorite: “To try to be happy is to try to build a machine with no other specifications than it shall run noiselessly.”

In summer, they retreated to a cabin in the mountains of New Mexico, which Robert called Perro Caliente (Spanish for “hot dog”). They rode horses over 13,000-foot peaks, 1,000 miles a summer. During one night ride, Robert got knocked off his horse. “He was very thin anyway,” Frank said. “Here was this little bit of protoplasm on the ground, not moving. It was scary, but he was all right.”

On a road trip back to Caltech, Frank rolled the car into a ditch, breaking Robert’s arm. When Robert stopped at a store to get a sling, he came back with a bright red one, to cheer up his little brother, who he knew was feeling bad about the accident.

The world around them was fraught, with fascism on the rise in Germany, Italy and Spain. The Depression meant people were still out of work. Robert kept mostly aloof from politics, but Frank dived in. He married a UC Berkeley student who was a member of the Young Communist League, then joined himself. He admired the Communists for taking unemployment seriously — and for understanding the threats posed by Hitler and Mussolini. His personal tipping point was the treatment of Blacks at a Pasadena public pool: Blacks were allowed only on Wednesdays; the pool was drained before the whites came back on Thursday. Only the Communist Party seemed concerned.

Robert didn’t approve of Frank’s decision to join the party, and he didn’t approve of his wife, Jackie, either, referring to her as “that waitress.” He accused Frank of being “slow” because it took him what Robert regarded as too long to get his PhD. He called Frank’s marriage “infantile.” The feelings became mutual. Jackie later regarded Robert and his wife, Kitty, as pretentious, phony and tight.

Frank soon realized that he wasn’t cut out to be a Communist, and quit. He felt the party was too authoritarian, and not as interested in social justice as in petty bickering. (Robert never joined, although Kitty had been a party member.)

From quantum theory to atom smashers

The brothers were both working as physicists when the Japanese bombed Pearl Harbor in 1941. Robert, the theorist, was sharing the revolutionary physics of quantum mechanics with his American colleagues at Berkeley and Caltech, where he had joint appointments. Frank, a natural-born experimentalist, was working with Ernest Lawrence at Berkeley on the rapidly developing technology of particle accelerators — known to some as “atom smashers.”

Once it became clear that the enormous energy contained in the atomic nucleus could be used to build a bomb — and that Nazi Germany might well be doing just that — President Franklin Roosevelt approved a major American effort to beat them to it: the Manhattan Project. It came as a surprise to everyone when Gen. Leslie Groves tapped Robert as director. Seemingly overnight, the ethereal young man who enjoyed reading poetry in Sanskrit became the ringleader of the most concentrated collection of brilliant minds ever assembled — scientists summoned from around the world to a makeshift lab on a desolate New Mexico mesa, where they would build an atomic bomb to stop Hitler.

Frank, meanwhile, worked with Lawrence on what he called “racetracks” (officially calutrons) used to coax small but vital amounts of pure uranium-235 out of a dirty mix of isotopes by steering them in circles with magnets. Uranium-235, like plutonium-239, is easily split, just what was needed to set off a chain reaction. Since no one knew how to bring together a critical mass of the stuff to make an explosion, two designs were pursued simultaneously. The plutonium bomb acquired the nickname Fat Man; the uranium bomb was Little Boy.

Frank helped supervise an enormous complex for uranium separation at Oak Ridge, Tennessee. Frank liked Gen. Groves and Groves, in turn, liked Frank — and later defended him when he was booted from physics for his politics.

As the time to test the bomb approached, Frank joined his brother at the Trinity site, a dry scrubby desert formerly part of the Alamogordo Bombing Range. Frank, who saw his job (ironically enough) as a “safety inspector,” mapped escape routes through the desert and made sure workers wore hard hats.

Finally, on July 16, 1945, the go-ahead was given. After a long night on edge watching driving rain and lightning rage around “the gadget” — a Fat Man-style plutonium bomb perched on a 100-foot-tall tower — the proverbial (and literal) button was pushed.

The brothers lay together at the nearest bunker, five miles away, heads to the ground. Frank later described the “unearthly hovering cloud. It was very bright and very purple and very awesome … and all the thunder of the blast was bouncing, bouncing back and forth on the cliffs and hills. The echoing went on and on.…” The cloud, he said “just seemed to hang there forever.”

Frank and his brother embraced each other: “I think we just said: ‘It worked.’”

On August 6, 1945, Little Boy was dropped on the pristine city of Hiroshima — which had been deliberately untouched by US bombs, the better to assess the damage. In an instant, the city was all but flattened, people reduced to charred cinders, survivors hobbling around with their skin peeled off and hanging from their bodies like rags. An estimated 140,000 people were killed in the attack and in the months after, according to Japanese authorities.

Frank heard the news outside his brother’s office at Los Alamos. “Up to then I don’t think I’d really thought of all those flattened people,” he said. The US bombing of Nagasaki with Fat Man just days later brought the death toll even higher.

Some physicists saw their success as a moral failure. Still, many — including Frank and Robert — also hoped this new weapon would cause people to see the world differently; they hoped it would ultimately bring about peace. “Those were the days when we all drank one toast only,” Robert said: “‘No more wars.’”

Intolerable weapon

After the war, the brothers’ lives diverged, driven by circumstance, in ways that were painful to both.

Robert was a hero; he mingled easily with the powerful. Famously, he was Einstein’s boss — director of the Institute for Advanced Study in Princeton. He chaired a committee to advise the government on a new and vastly more powerful type of bomb — the hydrogen bomb. Rather than split atoms, it fused them, using the physics of stars. The H-bomb could be 1,000 times more powerful than Little Boy.

Robert’s committee voted unanimously against developing it. “The extreme dangers to mankind inherent in this proposal wholly outweigh any military advantage that could come from this weapon.” They described it as a “threat to the future of the human race which is intolerable.”

Frank, meanwhile, had joined the physics department at the University of Minnesota, building detectors to catch cosmic rays streaming from space with equipment tethered to balloons he frequently lost but chased gamely through Cuban forests and other remote locations. He was excited about their discovery that the cosmic ray particles were not merely protons, as people had assumed, but the nuclei of many elements — from hydrogen to gold — implying that some were forged in supernova explosions.

At the same time, he was giving speeches “all over the map,” as he put it, trying to educate the public about nuclear bombs, trying to explain what 1,000 times more powerful really meant. He spoke to bankers, civic associations, schools. He argued that so-called “smart” people weren’t all that different from everyone else. The mistrust of the “hoi polloi,” Frank thought, stemmed largely from the tendency of people to credit their own success to a single personal characteristic, which they then “idolize” and use to measure everyone else by the same yardstick.

He believed people would educate themselves if they thought their voices mattered. “All of us have seen, especially during the war, the enormous increase in the competence of people that results from a sense of responsibility,” he said. Building the “racetracks” during the war had required training thousands of people “fresh from farms and woods to operate and repair the weirdest and most complicated equipment.”

Soon, his physics career was cut short. The FBI had been keeping tabs on both brothers for years, pausing only for the war, when military intelligence took over. Agents followed them everywhere, tapped their phones, planted microphones in their houses.

In 1949, Frank received a summons to appear before the House Un-American Activities Committee (HUAC), where he refused to take the fifth, but also refused to testify about anyone other than himself. He was effectively fired from the University of Minnesota physics department, leaving the chair’s office in tears.

Attempts to find work elsewhere were blocked at every turn, despite support from multiple Nobel laureates, Gen. Groves and even H-bomb enthusiast Edward Teller. Finally, an FBI agent told Frank flat out: If he wanted a job, he had to cooperate. “Then I realized what the wall was.”

Out of options, and having just purchased a ranch to live on “someday,” Frank and Jackie became serious cattle ranchers, learning from neighbors and veterinary manuals. (The FBI was right on their tails, pestering neighbors for information, suggesting they were broadcasting atomic secrets to Mexico.) All the while, Frank thought and wrote about physics and peace, civil rights, ethics, education and the critical role of honesty in science and public life.

Robert did not approve of any of Frank’s activities. He thought there wasn’t time to bring the public in on the debate; he thought he could use his fame and power to influence policy in Washington toward peaceful ends. Frank expressed his disgust at what he considered his brother’s futile and elitist approach. Robert made it clear that he thought the idea of becoming a rancher was a little silly — as well as beneath Frank.

Frank felt he could no longer reach him. “I saw my bro in Chicago,” Frank wrote his best friend Robert Wilson at Cornell in an undated letter probably from the early 1950s. “I fear that I merely amused him slightly when, in brotherly love, I told him that I was still confident that someday he would do something that I was proud of.”

A man destroyed

Robert’s now-famous downfall was swift. Many great books have been written about the subject (not to mention Christopher Nolan’s colossal film); in effect, he was punished for his opposition to the H-bomb, probably his arrogance and naivete as well. After a series of secret hearings, his security clearance was revoked; he was, by all accounts, a ruined man.

It wasn’t something Frank liked to talk about. “He trusted his ability to talk to people and convince them,” Frank said. “But he was up against people that weren’t used to being convinced by conversation.”

Some of Robert’s most poignant testimony during the hearings involved Frank. Asked if his brother had ever been a Communist, Robert answered: “Mr. Chairman … I ask you not to press these questions about my brother. If they are important to you, you can ask him. I will answer, if asked, but I beg of you not to ask me these questions.”

The broader tragedy for both brothers was that the creation of the world’s most fearsome weapon of mass destruction — a thing too horrible ever to use — didn’t much change how people viewed war. The H-bomb was just another weapon.

“What undid him,” Frank said, “was not just his fall from official grace, but the fact that this fall represented a defeat for the kind of civilized behavior that he had hoped nations would adopt.”

Robert died at the age of 62, in 1967. Frank’s last memory of his brother is poignantly familial. Robert was lying in bed, in great pain from throat cancer. Frank lay down beside him and together they watched Perry Mason on TV.

A new path

While Robert was being politically destroyed, Frank had started teaching science in a one-room schoolhouse. Before long, students from Pagosa Springs, Colorado, were winning the state science fairs. Eventually allowed into academia by the University of Colorado in 1959, Frank promptly built a “library of experiments” out of equipment scavenged from other labs.

That “library” in time grew into a vast public playground of scientific stuff housed in the abandoned Palace of Fine Arts in San Francisco. Exhibits — sometimes sophisticated and delicate — were meant to be played with, even broken; no guards stopped people from touching anything, no rules prevented theft — and remarkably, there was almost none. He called it an Exploratorium so people wouldn’t think it was a “museum” where good behavior was expected (although he liked the idea that “no one flunks a museum”). Top scientists and artists from around the globe contributed time and talent. Barbara Gamow, wife of the physicist George Gamow, painted a sign to hang over the machine shop: Here is Being Created an Exploratorium, a Community Museum Dedicated to Awareness.

In the end, I like to think Frank proved his brother (and most everyone else) wrong about the willingness of everyday people to engage and learn. The “so-called inattentive public,” he’d said, would come to life if people didn’t feel “fooled and lied to,” if they felt valued and respected. And if people got addicted to figuring things out for themselves, they’d be inoculated against having to take the word of whatever bullies happened to be in power. Society could tap into this collective wisdom to solve pressing global problems — the only way he thought it could work.

Today, Exploratorium-style science centers exist in some form all over the globe.

I count myself as one of Frank’s many thousands of addicts, hooked on science (a subject I’d found boring) the minute I met him in 1971. (In a weird resonance with today, my first foray into journalism was a piece on the Soviet invasion of Czechoslovakia for the New York Times Magazine.) I was interested in peace, not physics. Frank talked me into writing for him, explaining optics and wave mechanics to the public. My first editor was Jackie. Over the years, Frank and I spent endless hours chatting about life, art, science and his family, including his brother.

Nolan’s film Oppenheimer doesn’t offer much insight into Robert’s thoughts on science and peace or science and human morality. However, Robert did think and talk about these ideas, many of which are collected in his 1954 book Science and the Common Understanding, as well as other places.

Frank continued to get upset (and a little drunk) every August 6, the day Hiroshima was bombed. He’d rub his forehead hard, as if he was trying to rub something out. He had much the same reaction to many previous dramatizations of the Oppenheimer story, because he thought they focused too much on the fall of his brother, rather than on the failure of attempts to use the horror of the bomb to build a warless world.

Frank’s fierce integrity permeated our work together: He refused to call me writer/editor because he said that meant writer divided by editor. Instead, I was his Exploratorium Expositor.

If someone said, “It’s impossible to know something, or impossible to adequately thank someone,” he’d argue: It’s not impossible, it’s only very, very, very hard.

No matter what impossible thing Frank was trying to do, he refused to be stopped by so-called “real world” obstacles. “It’s not the real world,” he’d rage. “It’s a world we made up.” We could do better. In fact, so many of what we came to call “Frankisms” seem more relevant today than ever:

“The worst thing a son of a bitch can do to you is turn you into a son of a bitch.”

“Artists and scientists are the official noticers of society.”

“If we stop trying to understand things, we’ll all be sunk.”

Navigating the dark side of science, I think, will require attending closely to all of these. The “real world” we’re presented with is not the way things have to be. We shouldn’t become sons of bitches. We can never stop noticing or trying to understand.

Sunday, March 3, 2024

Losing the connection between the Andes and the Amazon: A price of peace in Colombia

The South American country, where the biodiversity of the Andes meets that of the Amazon, is losing the great natural wealth of some 1,500 square kilometers of forest each year, mainly in areas formerly under guerrilla control

In 2016, the same year the Colombian government and guerrillas of the Revolutionary Armed Forces of Colombia (FARC) agreed to end a war that had lasted almost half a century, the forests that make northwestern South America one of the most biodiverse places on the planet began to vanish. The demise of a conflict that had claimed the lives of at least 450,664 people marked the beginning of an environmental tragedy: In 2016 alone, deforestation increased 44 percent over the previous year.

“Colombia is now experiencing the consequences of the power vacuum left by the FARC over large parts of its territory,” warned ecologist Nicola Clerici of the University of Rosario in Bogota and colleagues in 2018. For decades, the war had slowed colonization in the south of the country and impeded deforestation — a phenomenon termed “gunpoint conservation.” After the peace agreement, the dynamics changed.

Colombia is now losing an average of 1,500 square kilometers of forest each year, an area 25 times the size of the island of Manhattan. About 65 percent of this is Amazonian forest. The forests are replaced by land for cattle ranching and agriculture, or they are simply set on fire so that the land can be fenced and sold. In 2018 alone, fires in biodiversity hotspots increased sixfold over the previous year.

Most of this deforestation is concentrated in the areas formerly controlled by the FARC, which include a 500-kilometer-long strip of land where the foothills of the Andes Mountains and the Amazon lowlands meet — a place that is a passageway for thousands of species, an area for genetic exchange between different populations of the same species, and a region supporting an extensive network of rivers that flow down from the mountains to feed the Amazon basin.

Beyond deforestation: the loss of connectivity

So far, political, media and even scientific attention and concern, both in Colombia and globally, has focused on the deforestation that is advancing in the Amazon itself. But Clerici and his colleagues, geographer Paulo Murillo of the University of Tolima in Ibagué and ecologist Camilo Correa-Ayram of the Pontifical Javierian University in Bogotá, are trying to draw attention to the problem that largely goes unnoticed: Deforestation is causing the loss of ecological connectivity between Andean and Amazonian forests.

The consequences of interrupting a biodiversity highway that has operated since the start of the Miocene, some 23 million years ago, are unknown, says Correa-Ayram. “We need to know what future trajectory this phenomenon is going to take,” he says.

The three scientists set out to analyze the extent of the loss of connectivity — the degree to which terrain impedes the movement of species between patches of resources — in forest areas in the Andes-Amazon Transition Belt, as the region is known. When ecosystems maintain high connectivity, animal species can freely feed, reproduce and migrate, as well as cycle nutrients, pollinate plants and disperse plant seeds.

The researchers used an index to estimate the spatial and functional connectivity between different forest patches — a measure they term “connected habitat.” Traditionally, analyses calculate only habitat loss, which oversimplifies ecosystem health. Think of a city’s power grid: It is one thing to lose power in 20 percent of the city and quite another to have that 20 percent loss concentrated in hospitals, railway operations and other crucial centers. In a similar manner, integrating variables like spatial patterns of lost habitat and the ability of species to continue to move around provides a better diagnosis of habitat health.

The findings, published in Global Ecology and Conservation in 2022, reported that the loss of habitat in the Colombian Andes-Amazon region between 2000 and 2020 was 13 percent, while the loss of connected habitat was higher still, at 18 percent. Both deforestation and connected habitat loss have accelerated since 2016, coinciding with the end of the armed conflict. “This result is worrisome because it indicates that well-connected patches are more fragmented and isolated, affecting the natural connections between the Andes and Amazon biogeographical regions and the movement ability of species,” the authors wrote.

This is bad news for the woolly monkey (Lagothrix lagothricha), which eats more than 200 types of plants and, like the Colombians, has learned to adapt to, and live in, a wide range of temperatures, from the hot lowland Amazonian rainforests to the cold Andean cloud forests. The loss of connected habitat will greatly restrict and fragment its home.

It is bad news also for guácharos (Steatornis caripensis), birds that travel at night from caves in the Andes mountains to the Amazon forests in search of a variety of fruits; it will mean longer journeys or changes to their diets. And for jaguars, which travel hundreds of kilometers back and forth between the Amazon and Andes forests in search of mates or food. And similarly for each of the thousands of species that live in the region.

Distances as small as four meters — such as those created by roads or power lines — are enough to become territorial barriers for some species, write ecosystem scientist Yadvinder Malhi of the University of Oxford and colleagues in an article in the Annual Review of Environment and Resources, in which they describe the human-caused factors currently affecting tropical forests.

A look into the past

Understanding the importance of this connection between the Andes and the Amazon requires a trip back in time to answer a question: Why is northwest South America one of the most biodiverse places on the planet?

“What we know is that the Amazon and the Andes Mountains are very interconnected, and the great diversity we see in the western Amazon is due to that interaction,” says Carina Hoorn, a geologist and paleoecologist at the University of Amsterdam, who traveled to Caquetá in southern Colombia, one of the most deforested areas of the country, to complete her master’s thesis in the 1980s. Hoorn has combined information from different fields — molecular biology, palynology, geology and phylogenetics — to try to understand the origin of biodiversity in the Amazon, a story in which the Andes played a leading role.

The story begins with a monumental collision between tectonic plates, mainly the South American plate and the Nazca plate, which gave rise to the majestic Andes Mountains. During the same era in which the dinosaurs became extinct, the end of the Cretaceous — about 100 million to 66 million years ago — these plates began to collide (Hoorn often compares them to two Mars bars squeezing against each other). It was an epic event, but in slow motion: Tectonic plates advance at an average speed of 1.5 centimeters per year. As they crashed and rode over each other, they caused folding in the crust that formed the mountains.

The southern part of the Andes, in present-day Argentina and Chile, and the center, in present-day Bolivia and Peru, formed first. The northern part, which corresponds to Ecuador and Colombia, began to rise some 23 million years ago and also involved interaction with the Caribbean tectonic plate. At this time, northern South America was a vast wetland known as the Pebas System, composed of deep lakes and swamps connected to the Caribbean Sea, as Hoorn and coauthors describe in the 2023 Annual Review of Earth and Planetary Sciences.

When the Andean mountains reached a critical elevation of more than 2,000 meters (more than 6,500 feet), they began to drastically alter the regional climate as rainfall increased — which coincided with a drop in global sea level. More rain and rivers rolling down the mountains meant more erosion and more washing of sediments and nutrients into the lowlands, into the Amazon. These sediments formed the basis for an explosion of diversity on the western side of the Amazon.

The Andes altered the entire landscape of northern South America. The ancient Pebas System was transformed into the Amazon River. The reorganization of the tectonic plates also caused the closure of the isthmus of Panama about 3.5 million years ago, leading to the Great Biotic American Exchange, in which previously isolated species migrated from the north to the south, and vice versa.

“To understand the Amazon, you have to understand the Andes-Amazon relationship,” Hoorn stresses. In terms of plants alone, it is estimated that the Amazon rainforest harbors some 50,000 species. And the Andes, occupying only 0.6 percent of the Earth’s surface, is home to 10 percent of the world’s vascular plant diversity — some 30,000 species. “The Andean mountains played a pivotal role in generating the biodiversity that colonized various regions of the Neotropics,” write Oscar Alejandro PĂ©rez, an evolutionary biologist at the Royal Botanic Gardens, Kew, in England and his colleagues, in an article published in Trends in Plant Science.

Rethinking conservation strategies

Everything that happens in the Andes ends up affecting the rest of the Amazon ecosystem, biologist Dolors Armenteras Pascual often tells her students at the National University of Colombia, where she is director of the Landscape Ecology and Ecosystem Modeling research group.

Armenteras Pascual regrets that there is not enough local research and information to better understand these phenomena and rethink conservation strategies. “We need more local research to effectively understand what is going on,” she says. “If we don’t do that, we can’t give evidence-based policy recommendations.”

After several decades studying the effects of deforestation, she has recently become focused on the need to better understand effects on aquatic systems. Most of the sediments that provide vital nitrogen, phosphorus and other elements to the Amazon come down from the Andes, she notes. “They have to do with the primary productivity of the whole basin, with phytoplankton, fish, dolphins, you name it. Any disconnection between the Andes and the Amazon also implies that this aquatic system is destabilized,” she says.

Pablo Negret, a Colombian ecologist at the University of Bern, Switzerland, agrees that the connection between the Andes and the Amazon is extremely important. One of the research projects he is involved in aims to identify which areas in the Andes-Amazon Transition Belt should be prioritized for conservation. “Globally, protected areas are biased towards areas of little economic interest,” he says. If you say you are protecting a giant area of the Amazon, “everyone applauds you, but if you go and measure, the impact is almost null because in that place there is less pressure from deforestation.” Investing money in protecting an area where colonization is advancing can be more costly, Negret acknowledges, but it is also more effective in preserving forest and species biodiversity.

Erle Ellis, an environmental scientist at the University of Maryland and author of a review of human land use published in the 2021 Annual Review of Environment and Resources, adds another concern to this list: In the face of climate change, species are trying to adapt by moving to different habitats. “Almost all species have a need to move on a large scale. And in that situation, connectivity is even more important,” he says. But, he argues, the way ecoregions, and therefore protected areas, have been mapped by the authorities does not allow them to be modified as the climate changes.

With such concerns in mind, researchers have begun to focus on analyses that can help policymakers redefine their conservation and restoration priorities.

One example of this is a study conducted by Correa-Ayram, spatial data analyst Daniela Linero and ecologist Jorge Velásquez and published in late 2023. They analyzed which corridors linking national parks in Colombia would ensure better connectivity to support 26 species of forest-dependent birds.

The data showed that, by protecting 212,551 square kilometers of land between various protected areas — mostly in the Andean and Amazonian forests — and by investing in efforts to restore 79,203 square kilometers currently used for agriculture, Colombia’s forest cover would increase by 7 percent and connectivity by 14 percent.

However, 82 percent of those 79,203 square kilometers identified as high-priority patches of land to be restored are not being considered in current plans. “The reflection here is how to move from words to deeds,” says Correa-Ayram. “We have a number of scientific studies, but where is the implementation of the corridors?”

For Correa-Ayram, the challenge in the coming years will be to achieve other types of connectivity: one between what science says and what policy should do, and another with the communities that live in these territories, so that they are active participants in the efforts to save one of the most biodiverse corners of the planet.

Article translated by Debbie Ponchner

Tuesday, February 27, 2024

How is snow made? An atmospheric scientist describes the journey of frozen ice crystals from clouds to the ground

Some parts of the U.S. see well over 100 inches (2.5 meters) of snow per year. Edoardo Frola/Moment Open via Getty Images
Alexandria Johnson, Purdue University

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to curiouskidsus@theconversation.com.


How is snow made? – Tenley, age 7, Rockford, Michigan


The thought of snow can conjure up images of powdery slopes, days out of school or hours of shoveling. For millions of people, it’s an inevitable part of life – but you may rarely stop to think about what made the snow.

As a professor of atmospheric and planetary sciences, I’ve studied how ice crystals floating in the sky become the snow that coats the ground.

It all starts in the clouds.

Clouds form when air near the Earth’s surface rises. This happens when sunlight warms the ground and the air closest to it, just like the Sun can warm your face on a cold winter day.

As the slightly warmer air rises, it cools – and the water vapor in that rising air condenses to form liquid water or water ice. From that, a cloud is born.

You need just two things for snow to form.

Endless pathways

When temperatures are well below freezing on the ground, the clouds are primarily made of water in the form of ice. Under 32 degrees Fahrenheit – that’s zero degrees Celsius – the frozen water molecules arrange themselves into a hexagonal, or six-sided, crystalline shape. As ice crystals grow and clump together, they become too heavy to stay aloft. With the help of gravity, they begin to fall back down through and eventually out of the cloud.

What these ice crystals look like once they reach land depends on the temperature and humidity of the atmosphere. As the humidity – or the amount of water vapor in the cloud – increases, some of the ice crystals will grow intricate arms at their six corners. That branching process creates what we think of as the characteristic shapes of snowflakes.

No two ice crystals take the same path through a cloud. Instead, every ice crystal experiences different temperatures and humidities as it travels through the cloud, whether going up or down. The ever-changing conditions, combined with the infinite number of paths the crystals could take, result in a unique growth history and crystalline shape for each and every snowflake. This is why you’ve likely heard the saying, “No two snowflakes are exactly alike.”

Many times, these differences are visible to the naked eye; sometimes a microscope is required to tell them apart. Either way, scientists who study clouds and snow can examine a snowflake and ultimately understand the path it took through the cloud to land on your hand.

Snow crystals attached to a window.
It takes approximately one hour for a snowflake to reach the ground. LiLi/iStock via Getty Images Plus

Liquid water as glue

When snow falls from the sky, you don’t usually see individual ice crystals, but rather clumps of crystals stuck together. One way ice crystals aggregate is through what’s called mechanical interlocking. When ice crystals bump into each other, crystals with intricate branches and arms intertwine and stick to others.

This mechanism is the main sticking process in cooler, drier conditions – what people call a “dry snow.” The result is a snow perfect for skiing, and easily picked up by the wind, but that won’t hold together when formed into a snowball.

The second way to stick ice crystals together is to warm them up a bit. When ice crystals fall through a region of cloud or atmosphere where the temperature is slightly above freezing, the edges of the crystals start to melt. Just a tiny bit of liquid water allows ice crystals that bump into each other to stick together very efficiently, almost like glue.

The result? Large clumps of ice crystals falling from the sky, what we call a “wet snow” – less than ideal for hitting the slopes but perfect for building a snowman.

Snow formed in clouds typically reaches the ground only in winter. But almost all clouds, no matter the time of year or location, contain some ice. This is true even for clouds in warm tropical regions, because the atmosphere above us is much colder and can reach temperatures below freezing even on the warmest of days. In fact, scientists who study weather discovered that clouds containing ice produce more rain than those that don’t contain any ice at all.


Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to CuriousKidsUS@theconversation.com. Please tell us your name, age and the city where you live.

And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.

Alexandria Johnson, Professor of Atmospheric and Planetary Sciences, Purdue University

This article is republished from The Conversation under a Creative Commons license.

Our robot harvests cotton by reaching out and plucking it, like a lizard’s tongue snatching flies

Cotton in bloom in Oklahoma. John Elk/the image Bank via Getty Images
Hussein Gharakhani, Mississippi State University

Cotton is one of the most valuable crops grown in the U.S., with a harvest value of some US$7 billion yearly. It is cultivated across a crescent of 17 states stretching from Virginia to California and is used in virtually every type of clothing, as well as in medical supplies and home goods such as upholstery.

Cotton grows inside a hard, fibrous case called a boll. About 100 days after planting, the bolls mature and split open, revealing thousands of fluffy white fibers inside. Each boll contains 20 to 40 seeds with fibers attached to them, which is why the cotton plant’s fruit is called seed cotton.

Picking cotton manually, as is still done in some major producing countries, is a meticulous task. Workers have to bend to reach the bolls and can hurt their hands on hard, dry parts of the plants. To harvest the seed cotton, they have to grab and twist it to separate it from the boll without leaving fiber behind.

Starting in the 1930s, cotton farmers in the U.S. shifted from manual labor to large, heavy harvesters. Now the industry is entering a new stage that promises to be more efficient and precise.

I am an engineer and have nearly 20 years of research experience working on agricultural machinery. My current focus is on agricultural robotics and automation. During my Ph.D. program at Mississippi State University, I worked with Alex Thomasson, who heads the agricultural and biological engineering department and the Agricultural Autonomy Institute, to develop a robotic cotton harvester that picks cotton with less damage to the product and the soil where it grows.

A man stands in front of a cotton field, next to a wheeled machine with a computer screen on top and wires hanging from it.
Mississippi State University engineering professor Hussein Gharakhani with a prototype robotic cotton harvester. Hussein Gharakhani, CC BY-ND

Why use robotics?

Cotton farmers have economic, environmental and agricultural reasons to want a better option for harvesting. Traditional mechanical harvesters can be up to 14 feet long and weigh more than 30 tons. They remove cotton effectively without damaging the plants but also can cause problems.

One issue is prolonged fiber exposure. Cotton bolls don’t all mature at the same time; the first open bolls in a field may wait for up to 50 days to be picked, until more bolls around them ripen.

Another challenge is that harvesting machines compact the soil as they roll over it. This makes it harder for water and fertilizer to penetrate down to plant roots. And the machines cost roughly US$1 million apiece but are used for only two to three months each year.

Robotics is a potential solution that farmers are already using for other crops, such as fruits and vegetables. Harvesting robots use cameras and sensors to detect when crops are ready to pick and can remove them without damaging the plant.

For cotton, robotics offers more targeted picking of bolls that are ready to harvest. It produces better-quality cotton fiber by picking seed cotton as soon as the bolls open, without leaving it exposed to the weather. The robot targets the seed cotton and avoids touching other parts of the plant.

With robotic picking, cotton farmers don’t need to use defoliants to remove leaves from the plants prior to harvesting, which is a common practice now. And small, nimble robots don’t compress the soil as they move over it, so they help maintain soil health.

A large green machine drives through a cotton field with a man riding on an observation deck. The harvester is more than twice the man's height.
A mechanical harvester picking cotton in Alabama in 2017. Katie Nichols/Alabama Extension/Flickr

A bioinspired ‘picking hand’

Our work focuses on designing an end-effector for robotic cotton harvesting. An end-effector is a robotic hand that enables the robot to interact with other objects. Ours is a three-fingered version designed for delicate and efficient cotton picking. It draws inspiration from nature, mimicking the hunting prowess of a lizard.

Each finger is a 3D-printed structure that contains a moving belt with pins attached to it. The pins help the hand grasp and pull in the seed cotton. Like a lizard snatching prey with its sticky tongue, our end-effector’s three fingers approach the seed cotton delicately. On contact, the cotton fibers stick to the machine’s fingers, much as an insect sticks to a lizard’s tongue.

Next, the hand retracts quickly, like the lizard’s tongue. The end-effector keeps working to “swallow” the seed cotton, transferring it out of the plant. As the harvester picks and transfers seed cotton out of the plant, the end-effector touches parts of the cotton boll with remaining seed cotton multiple times to pick as much as possible.

A robotic harvester picks cotton in a field test.

To pick cotton efficiently, our robot has to do three things: detect bolls that are ready for harvest, determine exactly where they are located in a three-dimensional space and pick the cotton.

The robot uses a deep-learning algorithm that we have trained to recognize open bolls on cotton plants. It uses a stereovision camera to calculate their 3D spatial coordinates, which it transfers to the robotic arm. A control algorithm monitors each cotton boll to ensure that the robot picks as much seed cotton as possible.

Testing and results

So far, we have tested the robotic cotton harvester in the laboratory and in cotton fields. The detection system found 78% of ripe cotton bolls; the localization system calculated 3D coordinates for 70% of the detected bolls; and the picking system successfully harvested 83% of these bolls. Overall, the robot picked about 50% of the cotton bolls that were within its reach.

Our harvester picked cotton at a speed of 8.8 seconds per boll. If we can decrease this required time to 0.3 seconds and increase the robot’s efficiency to pick at least 90% of the cotton bolls it can reach, by optimizing the system and adding more arms on a robot, a fleet of 50 robots could harvest a cotton field as quickly as a mechanical harvester, with a comparable yield.

To improve the robot’s overall performance, we plan to adopt better artificial intelligence algorithms, improve our system’s camera and add another degree of movement to the robotic arm – for example, enabling the end-effector to rotate – to increase its dexterity.

A woman wearing a sun visor and with a cloth bag slung around her waist bends over plants in a cotton field.
A woman picks cotton at a plantation in Birlik, Uzbekistan. Vyacheslav Oseledko/AFP via Getty Images

We see great potential for our robot in major cotton-producing countries such as China, India, Pakistan and Uzbekistan, where cotton is currently picked by hand, often by women and children and sometimes under abusive conditions. One way to make this technology available for small farmers in low-income countries would be to make smaller, semi-autonomous robots that would require fewer sensors. Producing higher-value cotton with less damage to plants and soil could improve life for millions of people who earn their livings raising this global crop.The Conversation

Hussein Gharakhani, Assistant Professor of Agricultural and Biological Engineering, Mississippi State University

This article is republished from The Conversation under a Creative Commons license. 

Sunday, February 25, 2024

The hidden threat from rising coastal groundwater

OPINION: Sea level rise won’t hit just homes on shorefronts, but also the infrastructure beneath our feet

When people think about sea level rise, many picture scenarios like flooded coastlines in Florida or Bangladesh, and beachfront homes succumbing to erosion on the Outer Banks of North Carolina. But some of the most significant threats to our communities are going unnoticed, underground.

The ocean is in direct contact with coastal groundwater. If you’ve ever built a sandcastle on the beach, digging a moat that fills with water from below, you’ve experienced this firsthand. As sea level rises, coastal groundwater levels rise too.

Cities have a crucial network of underground infrastructure, including water pipes, sewer systems, stormwater drains, electrical and fiber-optic lines and support structures for roadways and buildings. As coastal groundwater rises in our urban areas, it can flood this subterranean network. Often, that water is salty and corrosive.

Infrastructure failure caused by groundwater rise is already happening in many places, necessitating attention and timely management. Affected areas are seeing flooded basements, structural damage to foundations, corroded rebar, an uptick in water main breaks and overwhelmed sewage treatment plants. They also suffer from excessive rutting and potholing of roadways as the supportive layers underground become saturated. Perhaps most worryingly, buried contaminants are being brought to the surface as rising waters interact with sewage infrastructure, old industrial spills and more.

I am a sea-level-rise flood modeler based in Honolulu, which hosts one of the nation’s longest-operating tide gauges, along with a network of monitoring wells dedicated to observing the rise, and increased salt concentration, of coastal groundwater. The tide gauge has seen a more than 20-centimeter rise in sea level since before World War I. Groundwater has been rising in step.

In 2017, for example, events related to the climate pattern known as El Niño temporarily elevated sea levels by up to 30 cm above tide chart predictions across the Hawaiian Islands. The groundwater in Honolulu rose by nearly 30 cm, too. While this wasn’t surprising to hydrologists, it surprised locals as water seeped up to the surface more than a kilometer from the shoreline. Globally, sea levels are expected to rise about a meter by 2100.

Honolulu is leading the way in researching the influence of rising sea levels on groundwater; researchers here published one of the earliest studies on the topic, in 2012. Today, our Board of Water Supply uses groundwater simulations to help maintain and upgrade infrastructure. And the Hawaii State Department of Health is tracking contamination.

Research published in 2020 suggests that nearly 90 percent of Honolulu’s active cesspools are already compromised during king tides. The health department is also concerned about the upward seepage of lead and hydrocarbons, as well as the possibility of methane-induced underground explosions. While the latter may sound alarmist, it’s a legitimate concern. When petroleum contamination from past spills is immersed in rising groundwater, anaerobic bacteria break it down, leading to methane production. The health department actively tracks unexplained underground explosions in Honolulu that are thought to be linked to this phenomenon.

Honolulu is particularly susceptible to groundwater rise because parts of the city were built on a wetland: During land reclamation projects in the early to mid-20th century, the area was filled with a thin layer of soil for development. Honolulu’s underground infrastructure lies within this thin and porous veneer. But Honolulu is not unique; many major coastal cities were also expanded onto reclaimed land, including San Francisco, Boston, New York, Los Angeles, Tokyo, Osaka, Mumbai, Hong Kong, Singapore, Amsterdam and many others.

In a review paper on this issue, my colleagues and I identified 1,546 coastal urban areas around the world that likely have “critically shallow” groundwater 1.5 meters or less below the surface — a depth known to cause damage to buried infrastructure. Approximately 1.42 billion people live in these areas.

Honolulu takes a proactive approach to identifying groundwater-related issues, particularly in areas like Waikiki, which has financial resources and economic incentives to manage the damage. Three distinct research groups are engaged in developing adaptation plans for Waikiki, all considering groundwater inundation specifically. They plan to elevate infrastructure and catch problems early, knowing that pumping groundwater back down (a common first response) can just cause more saltwater intrusion and subsidence.

Despite this work, a recent survey of Hawaii decision-makers showed that while most are concerned about sea-level and groundwater rise, only 9 percent put it as their top priority. In the US, the sectors overseeing infrastructure for transit and wastewater management lack the necessary resources for basic maintenance, let alone for addressing future challenges. Many low-lying coastal cities around the world have even fewer resources and, in turn, face a chronic and escalating deterioration of critical infrastructure.

Groundwater inundation has the potential to cause overwhelming amounts of damage and to exacerbate social inequalities. We need to proactively tackle the current and impending flood of problems.

Friday, February 2, 2024

More than a year after the death of an environmental activist, questions remain on the dangerousness of the Stop Cop City movement near Atlanta

A makeshift memorial in the South River Forest for environmental activist Manuel Terán. Cheney Orr/AFP via Getty Images
Michael K. Logan, Kennesaw State University and Jennifer Carson, University of Central Missouri

Manuel Terán was one of a few dozen environmentalist activists who joined a protest nearly three years ago against the clearing of about 300 acres of woodlands near Atlanta to construct a proposed police and firefighter training center that critics fear would lead to greater “police militirization.”

Since 2021, some of the activists that include civil rights advocates and Indigenous tribes have called themselves “forest defenders” and rallied under the mantra of “Stop Cop City” to block construction workers by sitting in trees and, in some cases, setting fires and damaging construction vehicles.

Local police have responded in force with batons and riot shields to subdue demonstrators who on one march in November 2023 were armed with tree saplings that they wanted to plant in cleared sections of the South River Forest.

But those protests turned deadly on Jan. 18, 2023, when Terán was shot and killed during a police raid at one of the makeshift camps set up by activists.

Local police claim Terán fired the first shot. But some activists dispute the official version and argue that Terán was surrendering when he was shot 57 times by six different police officers.

Either way, one thing is indisputable: Terán was the first environmental activist to be killed by police in U.S. history.

A little more than a year later, his death has brought renewed questions about the dangerousness of environmental extremism.

The threat of ecoterrorism

Since Terán’s death, multiple waves of raids by police have largely cleared the area of protesters.

More than 40 Stop Cop City movement protesters face domestic terrorism charges and another 61 protesters face Georgia racketeering charges for actions related to their involvement in the movement.

Those criminal actions, exceptions to the majority of nonviolent demonstrations organized by environmental activists, included damaging buildings, setting fires to police cars, and vandalism.

Although the radical environmental movement did not emerge in the U.S. until the 1970s, it has been considered by the FBI to be a domestic terrorist threat since the 1990s.

Protestors carrying large posters are marching through smoke and underneath a neon Coke sign.
Demonstrators protest the death of environmental activist Manuel Terán on Jan. 21, 2023 in Atlanta. Elijah Nouvelage for The Washington Post via Getty Images

Two, often overlapping, schools of thought formed the cornerstones of the radical environmental movement. Championed by Norwegian philosopher Arne Naess, the first is known as deep ecology and holds that everything in nature is of equal value. The second, championed by philosopher Peter Singer, holds that animals have inherent value and deserve moral equality on par with humans.

Some radical environmentalists believe that because nature and animals have equal value to humans, they are justified in destroying property to protect nature and wilderness from human-made harm. But as a whole, environmental activists, like American writer Edward Abbey, do not support violence as a tactic and instead prefer peaceful acts of civil disobedience.

As defined by the FBI, ecoterrorism is “the use or threatened use of violence” against innocent victims or property for environmental and political reasons.

In May 2004, for instance, John E. Lewis, the FBI deputy assistant director, testified before the U.S. Senate Judiciary Committee that radical environmentalists, such as the Animal Liberation Front and Earth Liberation Front, were among the “most serious domestic terrorism threats.”

Lewis estimated that since 1976 both groups and other splinter organizations were responsible for committing more than 1,100 criminal acts in the U.S., which resulted in about US$110 million in damages.

However, our research has consistently shown that the majority of crimes committed by radical environmentalists were aimed at property rather than people and are not as dangerous as they once were in the 1990s.

Of the 1,069 criminal incidents between 1970 and 2007 that were motivated to protest the destruction of the environment, the mistreatment of animals, or both, nearly 72% of such crimes targeted businesses, such as food retailers, restaurants and fur or leather processors. Though the attacks could have hurt people or endangered their livelihoods, only 7% were aimed at politicians and business people.

An August 2023 assessment of the 896 criminal incidents committed between 1995 and 2022 by members of a radical environmental group indicated that the most common tactic used was smashing windows. According to the assessment, 78% of these incidents did not involve a weapon. But of the 22% that did, the weapon of choice appeared to be some sort of incendiary device, the assessment showed.

But the actions of radical environmentalists and motivation to protect the environment and animals from harm are not without victims, as damages to property may mean a business is forced to close or lay off some of its workers. Our research has shown that their actions in the time period between 1970 and 2007 resulted in an estimated $194 million in damages to businesses and government property.

Effectiveness of criminal justice policies

For the most part, today’s radical environmental movement has moved away from tactics using property destruction and threats of sabotage and is now characterized by forms of civil resistance, such as tree-sitting and blockading roads.

Although a number of factors, such as burnout and post-9/11 security measures, are cited by criminologists as reasons for the changes in tactics, government actions have been one important factor.

For example, Operation Backfire, a 2004 police crackdown in Portland, Oregon, was credited for the disbandment of “the Family,” a group of environmental extremists that included members of the Animal Liberation Front and the Earth Liberation Front that were active in the late 1990s and early 2000s.

In their assessment, criminologists Sue-Ming Yang and I-Chin Jen determined that Operation Backfire was successful because the numbers of crimes committed in the name of the group were reduced as the FBI arrested members of the group under federal anti-terrorism laws.

The crackdown ultimately resulted in the arrest of more than a dozen people on charges ranging from arson and possession of a destructive device to destruction of an energy facility.

In addition, research further shows that enforcement of federal legislation targeting specific acts, such as the Animal Enterprise Terrorism Act, also helped decrease the number of criminal attacks against animal research facilities, processing plants and other agricultural operations.

But not all government actions have been good. In 2016, for instance, peaceful protests against the Dakota Access pipeline were confronted by North Dakota law enforcement officers who used water cannons and tear gas to stop unarmed activists. More than 300 people were injured.

Research suggests that targeted law enforcement policies and the general threat of imprisonment are effective at deterring criminal acts committed by extremist environmentalists.

But whether those law enforcement efforts can deter the self-proclaimed forest defenders from continuing their nearly three-year demonstration at the South River Forest remains an open question.The Conversation

Michael K. Logan, Assistant Professor of Criminal Justice, Kennesaw State University and Jennifer Carson, Professor of Criminal Justice and Criminology, University of Central Missouri

This article is republished from The Conversation under a Creative Commons license.